Monday, November 29, 2010

iOS and Android: The Odd Development Couple

We recently ported our app HeyTell from iPhone to Android, and found that we gained a little perspective in the process. Because it uses a large number of system features (native widgets, location, database, audio, network services), porting the app really required a deep understanding of each platform.

A great way to get an understanding of the strengths and weaknesses of any software platform is to port software from one platform to another. For example, in the early days of my programming life, I'd write a simple "Missile Command" game to get a feel for a specific platform.

Here are some of the various perspectives of the iOS and Android platforms, and how we view them differently after the port:

User Interface - iOS has the benefit of being based on a mature UI framework (Cocoa) and Android has had to play catch-up with features (like animated views). iOS has the edge here with some features -- table/list views in particular are much more full-featured, if a bit difficult at times. Interface Builder also is much more slick than anything available on Android (I just edit the XML files directly on Android), so I'd say iOS wins this one.

Application Framework - Android and iPhone have very different ways of looking at the world. Android tries to model an app as a loosely-coupled set of Services, Activities, and Content Providers, while iOS sandboxes each app like a traditional OS. I understand the rationale behind Android's design, but I think it confuses more than it delivers.

Performance - We've never had serious problems with performance, although iOS seems to have a snappier UI in general and do a better job with compositing and animation. Both platforms allow native code (Android via the NDK) for CPU-intensive code.

Language - Objective C does seem to have a steep learning curve and a lot of new concepts compared with Java - especially regarding memory management. However, if you look under the surface, Android has many of the same issues (look up "android memory leaks weak references"). But if you're experienced in Java, you'll have a lot fewer hurdles with things like threading on Android.

Third-Party Libraries - There are roughly equal numbers of iOS and Android libraries on GitHub, for instance. On iOS, you have easy access to any C/C++ library (without going through JNI), while on Android, you have easy access to the thousands of native Java libs. I'd say this one is a tie.

Development Tools - Eclipse is a great environment and is perfectly optimized for Java programming. XCode isn't bad either, and the experience is a bit more polished. I do really appreciate the command-line tools like adb you get on Android, however. My partner is a big fan of the Dalvik Debug Monitor Server (DDMS).

Documentation - Apple has great documentation, and you can find pretty much anything you want to know there or in its example code. The Android docs are not quite as comprehensive, IMHO. We do use Google Code Search to search the Android code base ourselves, which is very helpful at times. But you're going to spend a lot of time on Stack Overflow, no matter what you pick. :)

Market - One feature of the Android Market is that you can push an update at any time without review. This is really comforting from a developer's standpoint (maybe not so much from a user's, but we're happy about it). Android also lets users comment on their stack traces, which is really neat. Okay, sometimes the comments are not so nice, but often they add steps to reproduce - this is really helpful, especially when it seems like we see a new piece of handset hardware appear in our matrix every day and testing across all devices/OSes/firmware revisions/carriers/whizzbang modded ROMs on Android is unfortunately really tricky for a small, bootstrapped team.

Monetization - Because HeyTell is free, we don't have any perspective on pay vs. non-pay apps on either platform, but Apple's In App Purchase capability has served us well. In App purchases are really important for us, because not all users want or need all features, and we don't want to charge users for features they don't want or need. Our fingers are crossed that Google adds an IAP capability soon. In addition, on the advertising side, there really isn't anything on Android quite as turn-key as Apple's iAd. All points go to iOS here, at least for now.

Tuesday, November 9, 2010

Viral Marketing for Nerds and Data Junkies

Thanks for everyone who attended my Viral Marketing at 360iDev in Austin! Big thanks to John and Nicole for having us as speakers.

For everyone who asked, slides are below :)

Thursday, August 26, 2010

Steve & Jen Speaking at 360|iDev Austin in November

We attended 360|iDev San Jose in Spring of 2010 and had a great time — learned a lot, met a lot of really cool people, and got a chance to connect with fellow travelers on the indie iPhone developer scene. Great fun and a tremendous learning experience!

We enjoyed it so much, that when we heard "November in Austin," we knew we'd be there for sure. It seemed like a good idea to give back and share some of the things we've learned from the release of HeyTell Voice Messenger, so we both submitted talks — and both were accepted!

Steve will be presenting Viral Marketing by the Numbers where he'll bring a developer's perspective to marketing the freemium iPhone app HeyTell Voice Messenger and how it gained 100,000 users using a purely viral marketing model without paid ads or employing conventional PR.

He'll talk about the features and performance of viral vectors by the numbers, predicted vs. actual growth, and will draw some parallels between viral propagation of an app and nuclear reactions. The audience will hopefully take away additional ideas and strategies for successfully incorporating viral elements into their applications.

Jen's going to dig into The Reluctant SysAdmin: Managing the Server-side of a Client/Server iPhone App, where she'll talk about all the fun and not-so-fun things about managing the server-side of a client-server app with an emphasis on security, reliability, and survival (and sleep!) when you're small & indie.

She'll hit on some of the fantastic things about maintaining a server component (metrics, Push Notifications, App Store receipt handling, did we mention metrics?) as well as the not-quite-as-fantastic (24x7 system monitoring, data security, and attacker-thwarting, rolling upgrades for services that can't go down, the occasional sleepless night) and will then focus on processes, products and technologies that make this all easier for a small team to implement, including continuous integration strategies, use & abuse of Amazon Web Services (EC2), and open source solutions for security & monitoring.

As you can see, we're really excited about 360|iDev in Austin - if you're coming, can't wait to see you. If you're considering, hurry up and book it! If you're not, reconsider and book it anyway!

Tuesday, August 24, 2010

Gauging User Sentiment with Word Clouds

We just released the HeyTell Android Beta and, in the calm before the storm, wanted to take a little break and do something a little frivolous. Perfect time for word cloud creation! Why not take a look at frequency of the words users use to describe HeyTell for iPhone 2.0.3 when reviewing the app on the App Store?

So I popped over to iTunes connect, expanded user comments and saved as HTML. A little command line fu, like such:

grep "review-text" DownloadedComments.html |awk -F '\">|\<\/P' '{print $2}'

Copy and paste the output to, et voila, user sentiment made pretty:

Monday, July 26, 2010

Requirements Tracking For Total Slobs

I'm now working on an iPhone/mobile startup with just a handful of people, and we typically get things done via shouts, IMs, and emails. This works for us, but I used to work at a company which did things *much* more formally. We will refer to this way of doing things as (drumroll) The Process.

The Process goes as follows: Product Managers generate Functional Requirements which go to the Engineers which turn these into Design Requirements which go to the Developers which develop The Product which goes to QA who uses the Design Requirements to create a Test Plan which then gets sent to Integration Teams which use the Documentation generated from the Design Requirements to make the Installation Guide which then results in the Customer getting ... well, something.

This is a little heavyweight for the standard indie dev shop, but there's a good practice hidden here, which is the generation of Requirements. Why would you want to make actual Requirements when DESIGN.TXT in your home directory will do just fine? There are several reasons:
  • They encourage you to record design decisions, and act as high-level code documentation.
  • They give you a way to generate test plans - each requirement should be a testable feature of the product.
  • When doing a port to another platform, they let you know when you're done (when all the requirements are checked off)
  • They let the test team know when they're done (when all the requirements are checked off)
These all boil down to "scoping" your product. Any external party can look at the requirements of your application and get the gist of what's going on without looking at code, and if you do it right, they can test/document/port/translate/regress/whatever and know that they haven't missed anything.

Of course, no one is really going to go through much extra effort generating documentation when they could be making apps and making money. That's foolish. That's why I'm going to show you my bone-simple Requirements Generation Technique. Watch closely!

1. A requirement is defined in a source file (.c, .cpp, .m, .java etc) with a code comment. Here is an example:

// Requirement: When a Butterball is hit with a bullet, split it into two Niblets.

2. Generating a design document is done as follows:

% find . -name '*.[cm]' -print0 | xargs -0 grep Requirement: > design.txt

3. Doing a "Gap Analysis" (comparing two design docs) is done as follows:

% sdiff design1.txt design2.txt

With a little effort, you can pipe requirements to CSV files and upload to Google Docs so other team members can review, make test plans, etc.

Congratulations! You've just replaced thousands of dollars of expensive requirements-tracking tools and at least three middle managers! You've also taken a step to better documenting your code and your product so others can more easily play in your sandbox. You don't need an overweight version of The Process like our example bureaucratic organization, but it helps to have a little organization in whatever you do.

Monday, April 5, 2010

Top 10 Bolt-On Cocoa Touch Libraries

In the last few months of iPhone dev on apps such as HeyTell, we've learned a lot about how to save time and add features by taking advantage of third-party libraries. In no particular order, here are some of the easiest to integrate (thus "bolt-on"):

1. Reachability - Every iPhone developer should know about this. It's the Apple-approved way to check to see if network connectivity is available from your app. It helps to wrap this with your own code for generating helpful Alerts when the network bounces up and down.

2. SFHFKeychainUtils - The Keychain API may look scary, but it's useful too. How else will you store encrypted, backed-up key-value pairs that persist across uninstalls of your app? This wrapper API has just a handful of easy-to-understand methods.

3. Plug in an analytics API like the Medialets SDKs to capture information about your app at runtime. In just a few minutes you can be capturing app installs and start/stop events, a little more time gives you custom app events and lets you integrate ads into your app.

4. java-apns - Ashwin Phatak's Java library for push notification. Requires a bit of integration work (and a server component) but much better than rolling your own. (ok, so it's not a Cocoa Touch library per se - but it's essential if you're doing APNS in Java)

5. Combine your native code with HTML by using PhoneGap and iUI to make look-alike user interfaces in HTML, JavaScript, and CSS.

6. If you're a game developer you must have heard of OpenFeint, so there's no need to explain this popular social-media-enabling bolt-on library.

7. Appirater helps you get feedback on your app by requesting a review after a configurable amount of time or number of app runs. Just a few minutes to integrate.

8. The default HTTP client libraries sometimes don't cut it, especially when streaming or multi-threading. Try ASIHTTPRequest and get a wealth of features above and beyond what the standard NSURLRequest provides.

9. When building apps that parse XML from REST queries, you may want to try TouchXML which provides an easy-to-navigate DOM tree object from your XML documents. Don't like XML? Try Google's Protocol Buffers or Apache Thrift for more efficient and robust network protocol structures.

10. And when your project is ready to ship, give Hudson a try to automate your builds. The new Xcode 3.2 provides features that may help in archiving built products, but I think there's still value in doing a clean checkout and build from the repository (instructions for iPhone here)

We hope these give you some ideas on how to save precious mental CPU cycles on your next iPhone/iPod/iPad project!

Thursday, January 7, 2010

Reduce your micro-startup burn rate...and see the world, too!

At Voxilate, we've taken a novel approach to reducing capital expenditures while maximizing productivity and creativity: we're taking the show on the road and are putting our money where our mouths are--creating voice-activated applications for mobile devices while being mobile ourselves!

This is a bit easier to do as a micro-startup (also known as "Micro ISV"), given highly-available mobile broadband and ubiquitous wireless Internet connectivity, competitive hosting and "cloud" solutions, and the myriad online, hosted services at our beck and call these days.

Here's a quick rundown of tips we've found vital to our mobility so far (we will expand on these in later posts):

Mobile broadband: Don't leave home without it. We purchased a wireless broadband plan and wireless card that's plug-and-play with our mobile broadband-enabled CradlePoint MBR900 router. We also have a PepWave Surf personal wi-fi receiver that can harness available wi-fi and make it available to more than one team member or computer.

Network redundancy: Make sure you're bound to more than one network and/or cell provider. You want to always be able to call out, check email, and connect to remote systems with at least one of your team's phones or netbooks using wireless broadband cards or cell-phone tethering. We often switch between AT&T and Verizon services. Would be better to switch between three or four - but we're talking about belt-tightening, here!

Hardware: In addition to your mobile broadband card and portable routers, a good mix of laptops, external hard drives, and small form-factor systems like the Mac Mini will serve you well. You'll also want cigarette-lighter power adapters to power and charge your stuff - and, if there are more than one of you not driving while on the road, use the router in the car with the broadband card. Also remember to bring power strips, outlet expanders, Ethernet cables, thumb drives, extra chargers, connectors, and so on.

Internal Systems: You should have a source control system, build system, and bug system for development. What you choose to administer locally or remotely is up to you, but do make sure that everyone's got a copy of the source repository checked out and if you're self-hosting build & source control, ensure that you can swap build and source control systems from one laptop or mini-server to another in case of catastrophe. If you're going to be someplace for a day or two, make sure you check in your code. During this 'period of stability,' remember to also rsync (or some other replication method) to back up your critical systems to your hard drives as well as a secure off-site backup provider that you trust and uses encryption.

Hosting redundancy: Choose hosting providers you trust and who have good reputations - don't always go for the cheapest (although price doesn't always mean quality, either!). Look for hosting providers that provide data center geographic diversity. Augment with other providers - you want the ability to quickly bring your systems up in case of a hosting provider's catastrophic failure. Amazon's web services are excellent for this purpose--encrypt and backup your data to S3, build your backup systems with EC2 & EBS--and pay only when you need to bring them up or test (and you can bring them up in minutes, with simple shell scripts). Great for staging/development/pre-production servers, too.

System monitoring & Maintenance: You'll want to set up something to quickly alert you via email or SMS when remote systems go down - use a service like Pingdom and supplement with self-monitoring on your hosts. Sign up for system status and downtime alerts (if you're not added by default) for all of your providers. Follow their Twitter feeds and check your email. Do what you feel you need to do to keep peace of mind and security; script it, add it to crontab, and have it email you its results. For example, scan your web logs for unexpected traffic that doesn't 404. Monitor vulnerability alert RSS feeds for software you use (both locally and especially on your externally hosted systems). Use Snort and OSSEC. Use whatever tool(s) you love. I love elementary shell scripts. Lots of people love Nagios. Many adore splunk. Mix and match for great justice.

Delegation: Use services to do your bidding and spend your time doing what you do best. Take advantage of great services like Amazon's Mechanical Turk for quick, repetitive, or data entry type tasks and for graphic design expertise. Get a good accountant that can meet via phone or email. Use online fax and voice services to stay connected wherever you happen to be.

Mail: We use trusted family members and a mail receiving/scanning service, Earth Class Mail. You can view your mail online and have it scanned and/or snail mailed to you wherever you happen to be, singly or in batches. They even have an auto-deposit option for checks you receive. Also try to configure anything you can to send you bills and notices online--scanning costs can add up.

Digital and Physical Security: This is a biggie! When you're carrying your tech like a turtle on your back and depending on the wireless of others, an awareness of both physical and network security are vital. Don't connect to wireless networks you don't trust. Don't check your bank balance using hotel wireless, for example, and always check certificates (although that isn't any guarantee these days, unfortunately). Be careful what you download. Bring your own routers to ensure that you can connect to your local resources without going over the public Internet.

As far as the real world goes: Assume everything you have will be stolen and plan for the occasion. Make copies of all important documents and store with someone you trust. Categorize the importance of what you're lugging, then lock up the most valuable things and keep them on your person when you leave your vehicle for the night. Get into a routine, and make everyone crosscheck each other so you don't leave anything behind.

Short-term locations: Go beautiful, go off-season. Use sites like Check out executive long-term stay spots as well - if you plan ahead, you can often get a really nice condo in a great location for much less than you'd pay for a standard hotel room.

Make sure they've got broadband, and come prepared with all the things described above. Plan your stays around your work schedule - stay awhile if you're in deep development. You don't want to be on the road (well, with the tips above, you can be if you want to be!) when you've got a lot of coding or testing to do!

Trust, but verify: Verify your setup before you embark long-term. Use your network setup where you're currently at, then take it with you on the road. Try staying somewhere local for a week or more, near friends/family/business acquaintances so that you can easily offload equipment you find you don't really need.

These are just a few of the things we've done to reduce our micro-startup 'burn' while enjoying a spectacular view.